mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.LinearAlgebra.Projectivization.Subspace

Goal state before:
pp: K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
⊢ ∀ ⦃x : ℙ K V⦄, x ∈ ⊤ → x ∈ span Set.univ

Tactic:
intro x

Goal state after:
K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
x : ℙ K V
⊢ x ∈ ⊤ → x ∈ span Set.univ
Module: Mathlib.LinearAlgebra.Projectivization.Subspace

Goal state before:
pp: K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
s : Subspace K V
c : K
x : V
h₁ : x ∈ {x | ∀ (h : x ≠ 0), Projectivization.mk K x h ∈ s.carrier}
h₂ : c • x ≠ 0
⊢ Projectivization.mk K (c • x) h₂ ∈ s.carrier

Tactic:
by
      convert! h₁ (right_ne_zero_of_smul h₂) using 1
      rw [Projectivization.mk_eq_mk_iff']
      exact ⟨c, rfl⟩

Goal state after:
Module: Mathlib.LinearAlgebra.Projectivization.PSL.PSL2

Goal state before:
pp: F : Type u_2
inst✝ : Field F
hF : 4 ≤ Nat.card F
⊢ ∃ a, a ≠ 0 ∧ a ^ 2 ≠ 1

Tactic:
have : Finite F := (Nat.card_pos_iff.1 (by omega)).2

Goal state after:
F : Type u_2
inst✝ : Field F
hF : 4 ≤ Nat.card F
this : Finite F
⊢ ∃ a, a ≠ 0 ∧ a ^ 2 ≠ 1
Module: Mathlib.LinearAlgebra.SpecialLinearGroup

Goal state before:
pp: case inr
R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
g : SpecialLinearGroup R V
hR : Nontrivial R
b : Module.Basis (Module.Free.ChooseBasisIndex R V) R V := Module.Free.chooseBasis R V
⊢ g ∈ Subgroup.center (SpecialLinearGroup R V) ↔ ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑g = r • LinearMap.id

Tactic:
let := Module.Free.ChooseBasisIndex.fintype R V

Goal state after:
case inr
R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
g : SpecialLinearGroup R V
hR : Nontrivial R
b : Module.Basis (Module.Free.ChooseBasisIndex R V) R V := Module.Free.chooseBasis R V
this : Fintype (Module.Free.ChooseBasisIndex R V) := Module.Free.ChooseBasisIndex.fintype R V
⊢ g ∈ Subgroup.center (SpecialLinearGroup R V) ↔ ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑g = r • LinearMap.id
Module: Mathlib.LinearAlgebra.SpecialLinearGroup

Goal state before:
pp: case neg
R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
r✝ : ↥(rootsOfUnity (max (Module.finrank R V) 1) R)
r : Rˣ
hr : r ∈ rootsOfUnity (max (Module.finrank R V) 1) R
hV : ¬Module.finrank R V = 0
⊢ ↑↑⟨r, hr⟩ ^ Module.finrank R V = 1

Tactic:
rw [← ne_eq, ← Nat.one_le_iff_ne_zero] at hV

Goal state after:
case neg
R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
r✝ : ↥(rootsOfUnity (max (Module.finrank R V) 1) R)
r : Rˣ
hr : r ∈ rootsOfUnity (max (Module.finrank R V) 1) R
hV : 1 ≤ Module.finrank R V
⊢ ↑↑⟨r, hr⟩ ^ Module.finrank R V = 1
Module: Mathlib.LinearAlgebra.SpecialLinearGroup

Goal state before:
pp: R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
r : ↥(rootsOfUnity (max (Module.finrank R V) 1) R)
hR : ¬Subsingleton R
hV✝ : ¬Subsingleton V
hV : Nontrivial V
this✝ : FaithfulSMul R V
H : ∃ r_1, r_1 ^ Module.finrank R V = 1 ∧ ↑↑↑(centerEquivRootsOfUnity_invFun r) = r_1 • LinearMap.id
this : H.choose • LinearMap.id = ↑↑r • LinearMap.id
⊢ ∀ (a : V), ⋯.choose • a = ↑↑r • a

Tactic:
intro x

Goal state after:
R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
r : ↥(rootsOfUnity (max (Module.finrank R V) 1) R)
hR : ¬Subsingleton R
hV✝ : ¬Subsingleton V
hV : Nontrivial V
this✝ : FaithfulSMul R V
H : ∃ r_1, r_1 ^ Module.finrank R V = 1 ∧ ↑↑↑(centerEquivRootsOfUnity_invFun r) = r_1 • LinearMap.id
this : H.choose • LinearMap.id = ↑↑r • LinearMap.id
x : V
⊢ ⋯.choose • x = ↑↑r • x
Module: Mathlib.LinearAlgebra.QuadraticForm.Basis

Goal state before:
pp: case h
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁵ : LinearOrder ι
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : AddCommGroup N
inst✝¹ : Module R M
inst✝ : Module R N
Q : QuadraticMap R M N
bm : Basis ι R M
x : M
⊢ ∀ x_1 ∈ (bm.repr x).support.offDiag, ¬x_1.1 = x_1.2

Tactic:
intro x

Goal state after:
case h
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁵ : LinearOrder ι
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : AddCommGroup N
inst✝¹ : Module R M
inst✝ : Module R N
Q : QuadraticMap R M N
bm : Basis ι R M
x✝ : M
x : ι × ι
⊢ x ∈ (bm.repr x✝).support.offDiag → ¬x.1 = x.2
Module: Mathlib.LinearAlgebra.SpecialLinearGroup

Goal state before:
pp: case neg
R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
r : ↥(rootsOfUnity (max (Module.finrank R V) 1) R)
hR : ¬Subsingleton R
hV : ¬Subsingleton V
⊢ ⟨⋯.unit, ⋯⟩ = r

Tactic:
rw [not_subsingleton_iff_nontrivial] at hV
      have := Module.Free.instFaithfulSMulOfNontrivial R V
      simp only [← Subtype.val_inj, ← Units.val_inj, IsUnit.unit_spec]
      have H := mem_center_iff.mp (Subtype.prop (centerEquivRootsOfUnity_invFun r))
      suffices (H.choose • LinearMap.id : V →ₗ[R] V) = (r.val : R) • LinearMap.id by
        apply FaithfulSMul.eq_of_smul_eq_smul (α := V)
        intro x
        rw [LinearMap.ext_iff] at this
        simp only [LinearMap.smul_apply, LinearMap.id_coe, id_eq] at this
        rw [this x]
      rw [← H.choose_spec.2]
      simp [centerEquivRootsOfUnity_invFun]

Goal state after:
Module: Mathlib.LinearAlgebra.SpecialLinearGroup

Goal state before:
pp: R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
g h : ↥(Subgroup.center (SpecialLinearGroup R V))
hR : ¬Subsingleton R
hV✝ : ¬Subsingleton V
hV : Nontrivial V
this✝ : FaithfulSMul R V
Hg : ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑↑g = r • LinearMap.id := ⋯
Hh : ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑↑h = r • LinearMap.id := ⋯
Hgh : ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑↑(g * h) = r • LinearMap.id := ⋯
this : Hgh.choose • LinearMap.id = Hg.choose • LinearMap.id * Hh.choose • LinearMap.id
⊢ ∀ (a : V), Hgh.choose • a = (Hg.choose * Hh.choose) • a

Tactic:
intro x

Goal state after:
R : Type u_1
V : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup V
inst✝² : Module R V
inst✝¹ : Module.Free R V
inst✝ : Module.Finite R V
g h : ↥(Subgroup.center (SpecialLinearGroup R V))
hR : ¬Subsingleton R
hV✝ : ¬Subsingleton V
hV : Nontrivial V
this✝ : FaithfulSMul R V
Hg : ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑↑g = r • LinearMap.id := mem_center_iff.mp (Subtype.prop g)
Hh : ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑↑h = r • LinearMap.id := mem_center_iff.mp (Subtype.prop h)
Hgh : ∃ r, r ^ Module.finrank R V = 1 ∧ ↑↑↑(g * h) = r • LinearMap.id := mem_center_iff.mp (Subtype.prop (g * h))
this : Hgh.choose • LinearMap.id = Hg.choose • LinearMap.id * Hh.choose • LinearMap.id
x : V
⊢ Hgh.choose • x = (Hg.choose * Hh.choose) • x
Module: Mathlib.LinearAlgebra.SpecialLinearGroup

Goal state before:
pp: R : Type u_4
inst✝⁶ : CommRing R
V : Type u_5
inst✝⁵ : AddCommGroup V
inst✝⁴ : Module R V
inst✝³ : Module.Free R V
inst✝² : Module.Finite R V
ι : Type u_6
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
b : Module.Basis ι R V
g : ↥(center (Matrix.SpecialLinearGroup ι R))
a✝ : Nontrivial R
hV : Nontrivial V
hι : ¬IsEmpty ι
this✝ : FaithfulSMul R V
this :
  ↑↑(((centerCongr (toLin_equiv b)).trans centerEquivRootsOfUnity) g) • LinearMap.id =
    ↑↑(center_equiv_rootsOfUnity g) • LinearMap.id
⊢ ∀ (a : V),
    ↑↑(((centerCongr (toLin_equiv b)).trans centerEquivRootsOfUnity) g) • a = ↑↑(center_equiv_rootsOfUnity g) • a

Tactic:
intro x

Goal state after:
R : Type u_4
inst✝⁶ : CommRing R
V : Type u_5
inst✝⁵ : AddCommGroup V
inst✝⁴ : Module R V
inst✝³ : Module.Free R V
inst✝² : Module.Finite R V
ι : Type u_6
inst✝¹ : Fintype ι
inst✝ : DecidableEq ι
b : Module.Basis ι R V
g : ↥(center (Matrix.SpecialLinearGroup ι R))
a✝ : Nontrivial R
hV : Nontrivial V
hι : ¬IsEmpty ι
this✝ : FaithfulSMul R V
this :
  ↑↑(((centerCongr (toLin_equiv b)).trans centerEquivRootsOfUnity) g) • LinearMap.id =
    ↑↑(center_equiv_rootsOfUnity g) • LinearMap.id
x : V
⊢ ↑↑(((centerCongr (toLin_equiv b)).trans centerEquivRootsOfUnity) g) • x = ↑↑(center_equiv_rootsOfUnity g) • x
Module: Mathlib.LinearAlgebra.QuadraticForm.Signature

Goal state before:
pp: M : Type u_2
inst✝⁴ : AddCommGroup M
𝕜 : Type u_4
inst✝³ : Field 𝕜
inst✝² : LinearOrder 𝕜
inst✝¹ : Module 𝕜 M
Q : QuadraticForm 𝕜 M
inst✝ : FiniteDimensional 𝕜 M
V : Subspace 𝕜 M
hV : ∀ x ∈ V, Q x ≤ 0
Vp : Submodule 𝕜 M
hr : Module.finrank 𝕜 ↥Vp = sigPos Q
hVp : (QuadraticMap.restrict Q Vp).PosDef
W : Submodule 𝕜 M
hWp : W ≤ Vp
hWm : W ≤ V
⊢ ∀ x ∈ W, x = 0

Tactic:
intro x

Goal state after:
M : Type u_2
inst✝⁴ : AddCommGroup M
𝕜 : Type u_4
inst✝³ : Field 𝕜
inst✝² : LinearOrder 𝕜
inst✝¹ : Module 𝕜 M
Q : QuadraticForm 𝕜 M
inst✝ : FiniteDimensional 𝕜 M
V : Subspace 𝕜 M
hV : ∀ x ∈ V, Q x ≤ 0
Vp : Submodule 𝕜 M
hr : Module.finrank 𝕜 ↥Vp = sigPos Q
hVp : (QuadraticMap.restrict Q Vp).PosDef
W : Submodule 𝕜 M
hWp : W ≤ Vp
hWm : W ≤ V
x : M
⊢ x ∈ W → x = 0
Module: Mathlib.LinearAlgebra.QuadraticForm.Signature

Goal state before:
pp: 𝕜 : Type u_4
inst✝³ : Field 𝕜
inst✝² : LinearOrder 𝕜
ι : Type u_5
inst✝¹ : Fintype ι
w : ι → 𝕜
inst✝ : IsStrictOrderedRing 𝕜
s : Set ι
hs : ∀ i ∈ s, w i ≤ 0
⊢ ∀ x ∈ Pi.spanSubset 𝕜 s, (weightedSumSquares 𝕜 w) x ≤ 0

Tactic:
intro x

Goal state after:
𝕜 : Type u_4
inst✝³ : Field 𝕜
inst✝² : LinearOrder 𝕜
ι : Type u_5
inst✝¹ : Fintype ι
w : ι → 𝕜
inst✝ : IsStrictOrderedRing 𝕜
s : Set ι
hs : ∀ i ∈ s, w i ≤ 0
x : ι → 𝕜
⊢ x ∈ Pi.spanSubset 𝕜 s → (weightedSumSquares 𝕜 w) x ≤ 0
Module: Mathlib.LinearAlgebra.RootSystem.Finite.G2

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁶ : CommRing R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : AddCommGroup N
inst✝² : Module R N
P : RootPairing ι R M N
inst✝¹ : P.EmbeddedG2
inst✝ : DecidableEq M
⊢ ↑(allRoots P).toFinset ⊆ Set.range ⇑P.root

Tactic:
intro x

Goal state after:
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁶ : CommRing R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : AddCommGroup N
inst✝² : Module R N
P : RootPairing ι R M N
inst✝¹ : P.EmbeddedG2
inst✝ : DecidableEq M
x : M
⊢ x ∈ ↑(allRoots P).toFinset → x ∈ Set.range ⇑P.root
Module: Mathlib.LinearAlgebra.RootSystem.Finite.G2

Goal state before:
pp: case calc_4
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁸ : CommRing R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : P.EmbeddedG2
inst✝² : Finite ι
inst✝¹ : CharZero R
inst✝ : IsDomain R
i : ι
this : Fintype ι
B : P.InvariantForm
⊢ 2 * P.pairing i (short P) * (B.form (shortRoot P)) (shortRoot P) +
      P.pairing i (long P) * (3 * (B.form (shortRoot P)) (shortRoot P)) =
    (2 * P.pairing i (short P) + 3 * P.pairing i (long P)) * (B.form (twoShortAddLongRoot P)) (twoShortAddLongRoot P)

Tactic:
twoShortAddLongRoot_shortRoot

Goal state after:
case calc_4
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁸ : CommRing R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : P.EmbeddedG2
inst✝² : Finite ι
inst✝¹ : CharZero R
inst✝ : IsDomain R
i : ι
this : Fintype ι
B : P.InvariantForm
⊢ 2 * P.pairing i (short P) * (B.form (shortRoot P)) (shortRoot P) +
      P.pairing i (long P) * (3 * (B.form (shortRoot P)) (shortRoot P)) =
    (2 * P.pairing i (short P) + 3 * P.pairing i (long P)) * (B.form (shortRoot P)) (shortRoot P)
Module: Mathlib.LinearAlgebra.RootSystem.OfBilinear

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
B : M →ₗ[R] M →ₗ[R] R
x : M
hx : B.IsReflective x
hSB : B.IsSymm
⊢ B.IsOrthogonal ⇑(reflection ⋯)

Tactic:
intro y z
  simp only [reflection_apply, map_sub, map_smul, sub_apply,
    smul_apply, smul_eq_mul]
  refine hx.1.1 ?_
  simp only [mul_sub, ← mul_assoc, apply_self_mul_coroot_apply]
  rw [sub_eq_iff_eq_add, ← hSB.eq x y, RingHom.id_apply, mul_assoc _ _ (B x x), mul_comm _ (B x x),
    apply_self_mul_coroot_apply]
  ring

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.OfBilinear

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝³ : CommRing R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : IsReflexive R M
B : M →ₗ[R] M →ₗ[R] R
hNB : B.Nondegenerate
hSB : B.IsSymm
h2 : IsRegular 2
⊢ Injective fun x ↦ IsReflective.coroot B ⋯

Tactic:
intro x

Goal state after:
R : Type u_1
M : Type u_2
inst✝³ : CommRing R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : IsReflexive R M
B : M →ₗ[R] M →ₗ[R] R
hNB : B.Nondegenerate
hSB : B.IsSymm
h2 : IsRegular 2
x : ↑{x | B.IsReflective x}
⊢ ∀ ⦃a₂ : ↑{x | B.IsReflective x}⦄, (fun x ↦ IsReflective.coroot B ⋯) x = (fun x ↦ IsReflective.coroot B ⋯) a₂ → x = a₂
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Semisimple

Goal state before:
pp: ι : Type u_1
K : Type u_2
M : Type u_3
N : Type u_4
inst✝⁸ : Field K
inst✝⁷ : CharZero K
inst✝⁶ : DecidableEq ι
inst✝⁵ : Fintype ι
inst✝⁴ : AddCommGroup M
inst✝³ : Module K M
inst✝² : AddCommGroup N
inst✝¹ : Module K N
P : RootPairing ι K M N
inst✝ : P.IsCrystallographic
b : P.Base
i : ↥b.support
x : Matrix (↥b.support ⊕ ι) (↥b.support ⊕ ι) K
property✝ : x ∈ lieAlgebra b
hx : ⟨x, property✝⟩ ∈ H
j : ↥b.support ⊕ ι
⊢ (((toEnd K (↥H) (↥b.support ⊕ ι → K)) ⟨⟨x, property✝⟩, hx⟩ - 0 ⟨⟨x, property✝⟩, hx⟩ • 1) ^ 1) (u i) j = 0 j

Tactic:
by simpa using apply_sum_inl_eq_zero_of_mem_span_h i j hx

Goal state after:
Module: Mathlib.LinearAlgebra.SymmetricAlgebra.Basic

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
⊢ lift (ι R M) = AlgHom.id R (SymmetricAlgebra R M)

Tactic:
by
  apply algHom_ext
  rw [lift_comp_ι]
  ext
  simp

Goal state after:
Module: Mathlib.Logic.Hydra

Goal state before:
pp: case refine_1
α : Type u_1
r : α → α → Prop
inst✝¹ : DecidableEq α
inst✝ : Std.Irrefl r
s' s t : Multiset α
a : α
⊢ (∀ a' ∈ t, r a' a) ∧ a ∈ s + t ∧ s' = (s + t).erase a → (∀ a' ∈ t, r a' a) ∧ a ∈ s ∧ s' = s.erase a + t

Tactic:
rintro ⟨ht, ha, rfl⟩

Goal state after:
case refine_1
α : Type u_1
r : α → α → Prop
inst✝¹ : DecidableEq α
inst✝ : Std.Irrefl r
s t : Multiset α
a : α
ht : ∀ a' ∈ t, r a' a
ha : a ∈ s + t
⊢ (∀ a' ∈ t, r a' a) ∧ a ∈ s ∧ (s + t).erase a = s.erase a + t
Module: Mathlib.LinearAlgebra.Transvection.Generation

Goal state before:
pp: case left
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
e : V ≃ₗ[K] V
f : Dual K V
v : V
hv : v ∉ (↑e).fixedSubmodule
hf : map f (↑e).fixedSubmodule = ⊥
hfv : f (v - e v) = 0
hfv' : f (e v) = 1
ht : (↑e).fixedSubmodule ≤ (↑(transvection hfv)).fixedSubmodule
⊢ (↑e).fixedSubmodule ≤ (↑(transvection hfv * e)).fixedSubmodule

Tactic:
intro x

Goal state after:
case left
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
e : V ≃ₗ[K] V
f : Dual K V
v : V
hv : v ∉ (↑e).fixedSubmodule
hf : map f (↑e).fixedSubmodule = ⊥
hfv : f (v - e v) = 0
hfv' : f (e v) = 1
ht : (↑e).fixedSubmodule ≤ (↑(transvection hfv)).fixedSubmodule
x : V
⊢ x ∈ (↑e).fixedSubmodule → x ∈ (↑(transvection hfv * e)).fixedSubmodule
Module: Mathlib.MeasureTheory.Constructions.Cylinders

Goal state before:
pp: ι : Type u_2
α : ι → Type u_1
m : (i : ι) → MeasurableSpace (α i)
i : ι
S : Set ((x : ι) → α x)
t : Set (α i)
ht : MeasurableSet t
h : eval i ⁻¹' t = S
⊢ ∃ x, (∀ (i : ι), MeasurableSet (x i)) ∧ eval i ⁻¹' x i = S

Tactic:
refine ⟨fun j ↦ if hji : j = i then by convert! t else univ, fun j ↦ ?_, ?_⟩
  · by_cases hji : j = i
    · simp only [hji, eq_mpr_eq_cast, dif_pos]
      convert! ht
      simp only [cast_heq]
    · simp only [hji, not_false_iff, dif_neg, MeasurableSet.univ]
  · #adaptation_note /-- Before https://github.com/leanprover/lean4/pull/13166
    (replacing grind's canonicalizer with a type-directed normalizer), `grind` closed this goal.
    It is not yet clear whether this is due to defeq abuse in Mathlib or a problem in the new
    canonicalizer; a minimization would help. The original proof was: `grind` -/
    simp [h]

Goal state after:
Module: Mathlib.LinearAlgebra.Transvection.Generation

Goal state before:
pp: K : Type u_1
inst✝² : DivisionRing K
V : Type u_2
inst✝¹ : AddCommGroup V
inst✝ : Module K V
e : V ≃ₗ[K] V
u : V
hu : LinearIndependent K ![(↑e).fixedSubmodule.mkQ u, e.fixedReduce ((↑e).fixedSubmodule.mkQ u)]
y : V
hy : y ∈ (↑e).fixedSubmodule
z : V
hz : z ∈ K ∙ (e u - u)
hu' : y + z = e u
⊢ False

Tactic:
rw [Submodule.mem_span_singleton] at hz

Goal state after:
K : Type u_1
inst✝² : DivisionRing K
V : Type u_2
inst✝¹ : AddCommGroup V
inst✝ : Module K V
e : V ≃ₗ[K] V
u : V
hu : LinearIndependent K ![(↑e).fixedSubmodule.mkQ u, e.fixedReduce ((↑e).fixedSubmodule.mkQ u)]
y : V
hy : y ∈ (↑e).fixedSubmodule
z : V
hz : ∃ a, a • (e u - u) = z
hu' : y + z = e u
⊢ False
Module: Mathlib.MeasureTheory.Constructions.Cylinders

Goal state before:
pp: ι : Type u_2
α : ι → Type u_1
inst✝ : (i : ι) → MeasurableSpace (α i)
s : Set ((i : ι) → α i)
hs : MeasurableSet s
⊢ ∃ I t, I.Countable ∧ s = I.domRestrict ⁻¹' t

Tactic:
refine induction_on_inter generateFrom_squareCylinders.symm
    (isPiSystem_squareCylinders (fun _ ↦ isPiSystem_measurableSet) (by simp))
    ⟨∅, ∅, by simp⟩ ?_ ?_ ?_ s hs

Goal state after:
case refine_1
ι : Type u_2
α : ι → Type u_1
inst✝ : (i : ι) → MeasurableSpace (α i)
s : Set ((i : ι) → α i)
hs : MeasurableSet s
⊢ ∀ t ∈ squareCylinders fun i ↦ {s | MeasurableSet s}, ∃ I t_1, I.Countable ∧ t = I.domRestrict ⁻¹' t_1

case refine_2
ι : Type u_2
α : ι → Type u_1
inst✝ : (i : ι) → MeasurableSpace (α i)
s : Set ((i : ι) → α i)
hs : MeasurableSet s
⊢ ∀ (t : Set ((a : ι) → α a)),
    MeasurableSet t →
      (∃ I t_1, I.Countable ∧ t = I.domRestrict ⁻¹' t_1) → ∃ I t_1, I.Countable ∧ tᶜ = I.domRestrict ⁻¹' t_1

case refine_3
ι : Type u_2
α : ι → Type u_1
inst✝ : (i : ι) → MeasurableSpace (α i)
s : Set ((i : ι) → α i)
hs : MeasurableSet s
⊢ ∀ (f : ℕ → Set ((a : ι) → α a)),
    Pairwise (Disjoint on f) →
      (∀ (i : ℕ), MeasurableSet (f i)) →
        (∀ (i : ℕ), ∃ I t, I.Countable ∧ f i = I.domRestrict ⁻¹' t) →
          ∃ I t, I.Countable ∧ ⋃ i, f i = I.domRestrict ⁻¹' t
Module: Mathlib.LinearAlgebra.Transvection.Generation

Goal state before:
pp: case inr
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
e : V ≃ₗ[K] V
f g : Dual K V
v : V
a b : K
hv : LinearIndependent K ![(↑e).fixedSubmodule.mkQ v, e.fixedReduce ((↑e).fixedSubmodule.mkQ v)]
hf : (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ≤ ker f
hfv : f v = 1
hg : (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ≤ ker (f + g)
hfgv : (f + g) v = 1
hg0 : g ≠ 0
hne_top : (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ⊔ K ∙ v < ⊤
ha : ∀ (v_1 : V), (auxTransvection hf * e) v_1 - a • v_1 ∈ (↑e).fixedSubmodule ⊔ K ∙ v
hb : ∀ (v_1 : V), (auxTransvection hg * e) v_1 - b • v_1 ∈ (↑e).fixedSubmodule ⊔ K ∙ v
c : K := b - a
hc : c = b - a
key : ∀ (x : V), g (e x) • (v - e v) - c • x ∈ (↑e).fixedSubmodule ⊔ K ∙ v
hc0 : c ≠ 0
⊢ ⊤ ≤ (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ⊔ K ∙ v

Tactic:
intro x

Goal state after:
case inr
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
e : V ≃ₗ[K] V
f g : Dual K V
v : V
a b : K
hv : LinearIndependent K ![(↑e).fixedSubmodule.mkQ v, e.fixedReduce ((↑e).fixedSubmodule.mkQ v)]
hf : (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ≤ ker f
hfv : f v = 1
hg : (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ≤ ker (f + g)
hfgv : (f + g) v = 1
hg0 : g ≠ 0
hne_top : (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ⊔ K ∙ v < ⊤
ha : ∀ (v_1 : V), (auxTransvection hf * e) v_1 - a • v_1 ∈ (↑e).fixedSubmodule ⊔ K ∙ v
hb : ∀ (v_1 : V), (auxTransvection hg * e) v_1 - b • v_1 ∈ (↑e).fixedSubmodule ⊔ K ∙ v
c : K := b - a
hc : c = b - a
key : ∀ (x : V), g (e x) • (v - e v) - c • x ∈ (↑e).fixedSubmodule ⊔ K ∙ v
hc0 : c ≠ 0
x : V
⊢ x ∈ ⊤ → x ∈ (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ⊔ K ∙ v
Module: Mathlib.Topology.Order.WithTop

Goal state before:
pp: ι : Type u_1
inst✝² : LinearOrder ι
inst✝¹ : TopologicalSpace ι
inst✝ : OrderTopology ι
⊢ (Iio ⊤).OrdConnected

Tactic:
exact Set.ordConnected_Iio

Goal state after:
Module: Mathlib.Topology.Order.WithTop

Goal state before:
pp: ι : Type u_1
inst✝² : LinearOrder ι
inst✝¹ : TopologicalSpace ι
inst✝ : OrderTopology ι
d : ι
a : WithTop ι
ha : a ≠ ⊤
⊢ Tendsto (untopD d) (𝓝 a) (𝓝 (untopD d a))

Tactic:
lift a to ι using ha

Goal state after:
ι : Type u_1
inst✝² : LinearOrder ι
inst✝¹ : TopologicalSpace ι
inst✝ : OrderTopology ι
d a : ι
⊢ Tendsto (untopD d) (𝓝 ↑a) (𝓝 (untopD d ↑a))
Module: Mathlib.LinearAlgebra.Transvection.Generation

Goal state before:
pp: case inl.refine_1
K : Type u_1
inst✝³ : DivisionRing K
V : Type u_2
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : Module.Finite K V
n✝ : ℕ
e : V ≃ₗ[K] V
he : ∀ (a : K), ∃ x, e.fixedReduce x ≠ a • x
n : ℕ
hind :
  ∀ {e : V ≃ₗ[K] V},
    (∀ (a : K), ∃ x, ¬e.fixedReduce x = a • x) →
      finrank K (V ⧸ (↑e).fixedSubmodule) = n + 1 → e ∈ transvections K V ^ n * dilatransvections K V
h : finrank K (V ⧸ (↑e).fixedSubmodule) = n + 2
f : Dual K V
v : V
hv : LinearIndependent K ![(↑e).fixedSubmodule.mkQ v, e.fixedReduce ((↑e).fixedSubmodule.mkQ v)]
hf : (↑e).fixedSubmodule ⊔ K ∙ (e v - v) ≤ ker f
hfv : f v = 1
hv_notMem : v ∉ (↑e).fixedSubmodule
hrank : finrank K (V ⧸ (↑e).fixedSubmodule ⊔ K ∙ v) = n + 1
hn0 : n = 0
⊢ (auxTransvection hf)⁻¹ ∈ transvections K V

Tactic:
rw [inv_mem_transvections_iff]
          apply mem_transvections

Goal state after:
Module: Mathlib.MeasureTheory.Function.UniformIntegrable

Goal state before:
pp: α : Type u_1
β : Type u_2
ι : Type u_3
m : MeasurableSpace α
μ : Measure α
inst✝ : NormedAddCommGroup β
f g : ι → α → β
p : ℝ≥0∞
hf : UnifIntegrable f p μ
hg : UnifIntegrable g p μ
hp : 1 ≤ p
hf_meas : ∀ (i : ι), AEStronglyMeasurable (f i) μ
hg_meas : ∀ (i : ι), AEStronglyMeasurable (g i) μ
⊢ UnifIntegrable (f + g) p μ

Tactic:
intro ε hε

Goal state after:
α : Type u_1
β : Type u_2
ι : Type u_3
m : MeasurableSpace α
μ : Measure α
inst✝ : NormedAddCommGroup β
f g : ι → α → β
p : ℝ≥0∞
hf : UnifIntegrable f p μ
hg : UnifIntegrable g p μ
hp : 1 ≤ p
hf_meas : ∀ (i : ι), AEStronglyMeasurable (f i) μ
hg_meas : ∀ (i : ι), AEStronglyMeasurable (g i) μ
ε : ℝ
hε : 0 < ε
⊢ ∃ δ,
    ∃ (_ : 0 < δ),
      ∀ (i : ι) (s : Set α),
        MeasurableSet s → μ s ≤ ENNReal.ofReal δ → eLpNorm (s.indicator ((f + g) i)) p μ ≤ ENNReal.ofReal ε
Module: Mathlib.MeasureTheory.Function.UniformIntegrable

Goal state before:
pp: α : Type u_1
β : Type u_2
ι : Type u_3
m : MeasurableSpace α
μ : Measure α
inst✝ : NormedAddCommGroup β
f g : ι → α → β
p : ℝ≥0∞
hf : UnifIntegrable f p μ
hfg : ∀ (n : ι), f n =ᵐ[μ] g n
⊢ UnifIntegrable g p μ

Tactic:
intro ε hε

Goal state after:
α : Type u_1
β : Type u_2
ι : Type u_3
m : MeasurableSpace α
μ : Measure α
inst✝ : NormedAddCommGroup β
f g : ι → α → β
p : ℝ≥0∞
hf : UnifIntegrable f p μ
hfg : ∀ (n : ι), f n =ᵐ[μ] g n
ε : ℝ
hε : 0 < ε
⊢ ∃ δ,
    ∃ (_ : 0 < δ),
      ∀ (i : ι) (s : Set α),
        MeasurableSet s → μ s ≤ ENNReal.ofReal δ → eLpNorm (s.indicator (g i)) p μ ≤ ENNReal.ofReal ε
Module: Mathlib.MeasureTheory.Function.UniformIntegrable

Goal state before:
pp: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ : Measure α
inst✝ : NormedAddCommGroup β
f : α → β
hf : Integrable f μ
hmeas✝ : StronglyMeasurable f
ε : ℝ
hε : 0 < ε
htendsto : ∀ᵐ (x : α) ∂μ, Tendsto (fun M ↦ {x | ↑M ≤ ↑‖f x‖₊}.indicator f x) atTop (𝓝 0)
hmeas : ∀ (M : ℕ), AEStronglyMeasurable ({x | ↑M ≤ ↑‖f x‖₊}.indicator f) μ
⊢ HasFiniteIntegral (fun x ↦ ‖f x‖) μ

Tactic:
exact hf.norm.2

Goal state after: